This paper presents the results of a study on the effect of temperature on geopolymers manufactured using pozzolanic materials (fly ash). In this paper, we report on our investigation of the performance of porous geopolymers made with fly ash after exposure to temperatures from 600 °C up to 1000 °C. The research methodology consisted of pozzolanic materials (fly ash) synthesized with a mixture of sodium hydroxide and sodium silicate solution as an alkaline activator. Foaming agent solution was added to geopolymer paste. The geopolymer paste samples were cured at 60 °C for one day and the geopolymers samples were sintered from 600 °C to 1000 °C to evaluate strength loss due to thermal damage. We also studied their phase formation and microstructure. The heated geopolymers samples were tested by compressive strength after three days. The results showed that the porous geopolymers exhibited strength increases after temperature exposure.

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Geopolymer is cementitious binders that do not require the presence of ordinary Portland cement (OPC). Fly ash with geopolymer formulations prepared with mixing alumino-silicate with the alkaline activator solution has been applied as protective coating material that suitable for high temperature applications such as fire resistant panel. Geopolymer coating samples were cured at 70 °C for 24 hours before sintered using temperatures range from 600 °C to 1500 °C in order to increase strength and improve thermal properties. Curing conditions also have a significant effect on the development of mechanical strength in most cementitious systems. The chemical compositions, microstructure and FTIR were studied. Geopolymer coating samples cures to a glassy texture and effectively used to create a resistant surface. Fly ash geopolymer coating was improved the compressive strength of the coatings materials as high as 40 MPa. This technology develop a geopolymeric mix design that superior use as cementitious coatings with high thermal application.

The development of asbestos free brake pad composites using different fillers was investigated with a intention to substitute asbestos which is known hazardous and carcinogenic. Mechanical and morphology studies were made to clarify the mechanism for compressive strength, hardness and wear rate behavior of different filler of brake pad which were prepared by compression molding of mixture of filler (palm slag, calcium carbonate and dolomite) with phenolic as binder, metal fiber as reinforcement, graphite as lubricant and alumina as abrasive. The result showed that palm slag has significant potential to use as filler material in brake pad composite. The wear rate of palm slag composite was comparable with the conventional asbestos based brake pad. The result also supported by SEM micrograph.

Today, the building and construction sector demands environmentally friendly and sustainable protective coatings using inorganic coating materials for safe, non-hazardous, and great performance. Many researchers have been working on sustainable solutions to protect concrete and metal infrastructures against corrosion and surface deterioration with the intention of introducing green alternatives to conventional coatings. This article presents a review of developments of geopolymer pastes doped with different types of photocatalyst precursors including factors affecting geopolymer properties for enhancing coating with photocatalytic performance. Photodegradation using geopolymer photocatalyst has great potential for resolving harmless substances and removing pollutants when energized with ultraviolet (UV) light. Although geopolymer is a potentially new material with great properties, there has been less research focusing on the development of this coating. This study demonstrated that geopolymer binders are ideal precursor support materials for the synthesis of photocatalytic materials, with a significant potential for optimizing their distinctive properties.